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Adherence and invasion of mouse-adapted H pylori in different epithelial cell lines
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作者 Mao-Jun Zhang Fan-Liang Meng Xiao-Yun Ji Li-Hua He Jian-Zhong Zhang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第6期845-850,共6页
AIM: To assess the adhesion and invasion abilities of different mouse adapted H py/or/strains in different cell lines in vitro and investigate their effects on the virulence factors cagA and vacA. METHODS: The adher... AIM: To assess the adhesion and invasion abilities of different mouse adapted H py/or/strains in different cell lines in vitro and investigate their effects on the virulence factors cagA and vacA. METHODS: The adherence and invasion abilities of different N pylori strains in different epithelial cell lines were examined by the gentamycin protection assay. The null mutants of cagA and vacA were processed by direct PCR mutation method. The morphologic changes of different cell lines after N pylori attachment were examined by microscopy. RESULTS: The densities of adherence to and invasion into cells in vitro were different from those in the mouse infection experiments. 88-3887 strain could invade and adhere to cells stronger than SS1 and X47. All tested strains had better adhering and invasive abilities in SCG-7901 cell. CagA and vacA minus mutants had the same invasion and adherent abilities as their wild types. In all strains and cell lines tested, only AGS cell had the significant hummingbird phenotype after inoculation with the 88-3887 wild-type. CONCLUSION: Both the host cells and the bacteria play important parts in the invasion and adhesion abilities of Hpylori. CagA and VacA are not related to the ability of invasion and adhesion of Hpylori in different cell lines in vitro. 展开更多
关键词 HPYLORI adherence invasion Cell line
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Analysis on the Hydrochemical Characteristics of Groundwater and the Formation Reason in Wadi Bay Area of Libya
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作者 宋晓明 高翠萍 +1 位作者 Basher HM 杨悦锁 《Agricultural Science & Technology》 CAS 2010年第11期28-32,118,共6页
[Objective] The research aimed to analyze the formation reason of groundwater hydrochemical characteristics in the dry valley area of Wadi Bay of Libya and provide the scientific basis for the reasonable development u... [Objective] The research aimed to analyze the formation reason of groundwater hydrochemical characteristics in the dry valley area of Wadi Bay of Libya and provide the scientific basis for the reasonable development utilization and the environmental protection of groundwater.[Method] Took Wadi Bay area(dry valley)of Libya as the example,Piper trilinear graphic representation method,the descriptive statistics,the ion ratio coefficient method and the isotope evidence were used to systematically study the special hydrochemical characteristics of shallow groundwater in the arid climate condition in Wadi Bay area of Libya.[Result] The salt content of groundwater in the area was very high,and TDS was during 3.2-8.4 g/L.The main groundwater type was Cl·SO4-Na·Ca,then was Cl·SO4-Na·Ca·Mg.The concentrations of Cl-,Na+ and SO2-4,etc.in the groundwater in 70 km from the sea had the remarkable variation,but the concentrations of Mn2+,Ba2+,Si2+,NH+4 and NO-3 didn't have the same variation phenomenon.[Conclusion] The hydrochemical characteristics of shallow groundwater didn't relate to the dissolution infiltration reaction,the evaporation concentration effect and human activities.The major cause was the mixing effect of salt and fresh water in the invasion process of seawater. 展开更多
关键词 Hydrochemical characteristics of groundwater Seawater invasion Libya Arid area Wadi Bay
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Analysis of the Clinical Effect of Carisolv Minimally Invasive Gel in the Treatment of Pediatric Dental Caries
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作者 Chenting Qi 《Journal of Clinical and Nursing Research》 2024年第7期67-72,共6页
Objective:To study the clinical effect of Carisolv minimally invasive gel in the treatment of pediatric dental caries and its effect on pain.Methods:The research subjects of this paper were 113 cases of pediatric cari... Objective:To study the clinical effect of Carisolv minimally invasive gel in the treatment of pediatric dental caries and its effect on pain.Methods:The research subjects of this paper were 113 cases of pediatric caries admitted to the hospital from April 2021 to April 2023,which were divided into two groups by the randomized table method.The control group(n=56)received the traditional dental drilling treatment method,and the observation group(n=57)applied Carisolv minimally invasive gel for treatment.The pain sensitivity and clinical efficacy as well as the emotions and adherence of the children were compared between the two groups.Results:The emotional score(ES)of children in the observation group was significantly lower than that of the control group,and the Frankl Adherence Scale score was significantly higher than that of the control group,P<0.05;the pain sensitivity of children in the observation group was better than that of the control group,and the total clinical efficacy rate of children in the observation group was significantly higher than that of the control group,P<0.05.Conclusion:Carisolv minimally invasive gel has considerable efficacy in the treatment of pediatric caries,and it can alleviate pain and improve children’s emotional state and adherence to the program.Thus,it is suitable for wide clinical applications. 展开更多
关键词 Carisolv minimally invasive gel Pediatric caries Pain sensitivity Clinical efficacy adherence EMOTION
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Species and Distribution Characteristics of Alien Invasive Plants in Garden Greenbelt of Shijiazhuang City
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作者 Ruchun ZHANG Hongjun JIANG +1 位作者 Henan MENG Ruijun WANG 《Plant Diseases and Pests》 CAS 2023年第4期38-43,47,共7页
[Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,etc.in Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of publi... [Objectives]The paper was to investigate the garden greenbelt in 30 sample plots such as parks,roads,communities,etc.in Shijiazhuang City.[Methods]The species,abundance and frequency of weeds in the greenbelt of public gardens were recorded through point-line-surface investigation,and typical plants were sampled.[Results]There were 56 species of alien invasive plants in garden greenbelts of Shijiazhuang City,belonging to 44 genera and 20 families.In terms of life form,herbaceous plants were absolutely dominant,accounting for 92.8%of the total.The most alien invasive plants were native to America,accounting for 66.1%of the total.In terms of introduction path,the plants introduced artificially and unintentionally accounted for almost half.The species and quantity of alien invasive plants were related to the size of greenbelt area,the length of the build time of the surveyed plot,the composition structure of greenbelt and the level of green management and protection.There was larger distribution of alien invasive plants in the sample plots with large greenbelt area,long build time,herbaceous-dominated greenbelt and low level of green management and protection.Among the 56 alien invasive plants,3 plants were toxic.From the perspective of invasiveness,the alien invasive plants in the garden greenbelt of Shijiazhuang City could be divided into 5 levels:invasive alien species of malignant consequences,invasive alien species of severe consequences,invasive alien species of partial consequences,invasive alien species of average consequences,and invasive alien species to be observed.[Conclusions]This study will provide a reference for the prevention and control of alien plant invasion,and lay a foundation for the prevention and control of existing invasive plants. 展开更多
关键词 Alien invasive plant Garden greenbelt Distribution characteristics Shijazhuang City Introduction path
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Effects of Broussonetia papyrifera invasion and land use on vegetation characteristics in a tropical forest of Ghana
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作者 David M.Adigbli Alexander K.Anning +1 位作者 James K.Adomako Benedicta Y.Fosu-Mensah 《Journal of Forestry Research》 SCIE CAS CSCD 2019年第4期1363-1373,共11页
The purpose of this study was to evaluate the effects of Broussonetia papyrifera(paper mulberry)invasion and land use on the floristic composition of a dry semideciduous forest in Ghana.Forty-five plots(25 m×25 m... The purpose of this study was to evaluate the effects of Broussonetia papyrifera(paper mulberry)invasion and land use on the floristic composition of a dry semideciduous forest in Ghana.Forty-five plots(25 m×25 m each),distributed among three land uses-selectively logged(SL);abandoned farmlands(AF);and an undisturbed reference(RF)-were surveyed.Results showed lower tree species richness(S),diversity(H’),evenness(S)and basal area(BA)in the SL(46,0.78,0.32 and 269.12 m2 ha-1,respectively)and AF(40,0.53,0.45,and 131.16 m^2 ha^-1)sites compared to the RF site(79,2.66,0.87,963.72 m^2 ha^-1).Similar patterns were found at the shrub layer,but no differences were observed at the herb layer.Non-metric multidimensional scaling ordination revealed distinct species composition among the land uses.The two disturbed habitats,SL and AF,were associated with increased B.papyrifera invasion particularly in the overstory,with importance value index and mean relative density of 45 and 65.03%,and 42 and 53.29%,correspondingly.However,the species was only sparsely represented in the RF site.Tree density of B.papyrifera correlated negatively with H’,S,E,BA,and native tree density and richness.These findings highlight the strong link between human land use(i.e.,logging and slash-andburn farming),invasion,and vegetation characteristics,and suggest the need to limit these disturbances to conserve biodiversity within tropical forest ecosystems. 展开更多
关键词 Afram HEADWATERS FOREST RESERVE Broussonetia papyrifera FOREST COMMUNITY characteristics Human-caused disturbances Plant invasion
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Motivation dimensions for running a marathon:A new model emerging from the Motivation of Marathon Scale(MOMS) 被引量:2
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作者 Sima Zach Yan Xia +3 位作者 Aviva Zeev Michal Arnon Noa Choresh Gershon Tenenbaum 《Journal of Sport and Health Science》 SCIE 2017年第3期302-310,共9页
Purpose:The aim of this study was to test and expand the Motivation of Marathoners Scale(MOMS) model(Masters et al.,1993).Methods:The MOMS questionnaire was distributed to 306 male and female marathon runners(a... Purpose:The aim of this study was to test and expand the Motivation of Marathoners Scale(MOMS) model(Masters et al.,1993).Methods:The MOMS questionnaire was distributed to 306 male and female marathon runners(age range:20–77 years) with experience in marathon running(range:1–44 runs).A confirmatory factor analysis(CFA) revealed that the original Purpose:The aim of this study was to test and expand the Motivation of Marathoners Scale(MOMS) model(Masters et al.,1993).Methods:The MOMS questionnaire was distributed to 306 male and female marathon runners(age range:20-77 years) with experience in marathon running(range:1-44 runs).A confirmatory factor analysis(CFA) revealed that the original model failed to fit the data.Hence,exploratory factor analysis(EFA) was performed to test the best factorial solution for the current data,and a subsequent CFA was performed on the revised factorial structure.Then,a series of EFAs using maximum likelihood factor extraction method were performed.Results:The best structure solution for model-data fit resulted in 11 factors:psychological coping-emotional-related coping,psychological coping-everyday-life management,life meaning,self-esteem,recognition,affiliation,weight concerns,general health orientation-reduced disease prevalence and longevity,general health orientation-keep fit,competition,and personal goal achievement.Conclusion:This study provides a sound and solid framework for studying motivation for physically demanding tasks such as marathon runs,and needs to be similarly applied and tested in studies incorporating physical tasks which vary in mental demands. 展开更多
关键词 Exercise adherence MARATHON Motives Psychological characteristics
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The Effect Analysis of Different Experimental Methods for the Diagnosis of Invasive Pulmonary Aspergillosis in a Rat Model
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作者 Jiancong Lin Wenming Xu +4 位作者 Ming Li Yanli Xin Yuanyuan Niu Changran Zhang Zelong Guo 《International Journal of Clinical Medicine》 2013年第10期472-478,共7页
Background: Consensus on the most reliable assays to detect invasive aspergillosis from minimally or noninvasive samples has not been reached. In this study, we compared the efficacy of an enzyme-linked immunosorbent ... Background: Consensus on the most reliable assays to detect invasive aspergillosis from minimally or noninvasive samples has not been reached. In this study, we compared the efficacy of an enzyme-linked immunosorbent assay (ELISA) for galactomannan (GM) detection and quantitative real-time PCR assay (qRT-PCR) for the diagnosis of invasive pulmonary aspergillosis in a rat model. Methods: Neutropenic, male Sprague-Dawley rats (specific pathogen free;8 weeks old;weight, 200 ± 20 g) were immunosuppressed with cyclophosphamide and infected with Aspergillus fumigatus intratracheally. Tissue and whole blood samples were harvested on days 1, 3, 5, and 7 post-infection and examined with GM ELISA and qRT-PCR. Results: On day 7, A. fumigatus DNA was amplified from 14 of 48 whole blood samples from immunosuppressed infected rats: day 1 (0/12), day 3 (0/12), day 5 (6/12), day 7 (8/12) post infection. The sensitivity and specificity of the qRT-PCR assay were 29.2% and 100%, respectively. Receiver operating characteristic curve (ROC) analysis indicated a Ct cut-off value of 15.35, and the area under the curve (AUC) was 0.627. The GM assay detected antigen in sera obtained on day 1 (5/12), day 3 (9/12), day 5 (12/12), and day 7 (12/12) post-infection, and thus had a sensitivity of 79.2% and a specificity of 100%. The ROC of the GM assay indicated that the optimal cut-off value was 1.40 (specificity, 100%;AUC, 0.919). Conclusions: The GM assay was more sensitive than qRT-PCR assay in diagnosing invasive pulmonary aspergillosis in rats. 展开更多
关键词 INVASIVE PULMONARY ASPERGILLOSIS ASPERGILLUS GALACTOMANNAN ANTIGEN Quantitative Real-Time PCR Receiver Operating Characteristic Curve Rat Model
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Patient and Health System Related Factors Associated with Non-Adherence to Antihypertensive Medication among Patients at Chuka Referral Hospital, Kenya
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作者 Charity Gikunda Lucy Gitonga Paul Kamweru 《Open Journal of Clinical Diagnostics》 2021年第2期19-46,共28页
<b>Background: </b>Non-adherence to hypertensive medication continues to become a contributing factor to hypertensive complications like stroke, heart attacks, kidney disease heart failure. Associated fact... <b>Background: </b>Non-adherence to hypertensive medication continues to become a contributing factor to hypertensive complications like stroke, heart attacks, kidney disease heart failure. Associated factors to non-adherence are complex, are both internal and external to the patient and are difficult to extrapolate. Reports from Chuka referral hospital records showed that in 2016 there were 140 patients with hypertensive complications from 560 patients who attended the medical clinic that year. <b>Objective:</b> This study sought to explore the patient’s related factors that are associated with non-adherence to hypertension medication. <b>Methods:</b> This is a descriptive study design of (N = 575) people among them doctors, pharmacists, nurses, record officers and hypertension patients. Simple random sampling for patients (n = 81) and census sampling for health care workers was done and data collected using questionnaires and interview schedules between April 4<sup>th</sup>-May 30<sup>th</sup> 2019. Inferential and descriptive statistics were used for data analysis, aided by SPSS version 25. <b>Results:</b> 64% of the patients stated that they had missed medication. A significant negative correlation (<i>r<sub>pb</sub></i> = -0.23, <i>p</i> < 0.05) between age and non-adherence, significant positive correlation with monthly income (<i>r<sub>pb</sub></i> = 0.24, <i>p</i> < 0.04), non-significant relationship between non-adherence and marital status (<i>r<sub>pb</sub></i> = -0.13, <i>p</i> = 0.25) and patients’ level of education (<i>r<sub>pb</sub></i> = -0.06, <i>p</i> = 0.57). The overall model of health system related factors were found to be significant (<i>p</i><i> </i>< 0.05) and this included;quality of health service, physician patient relationship, stock out, health education, and availability of medicine (<i>p = </i>0.012). <b>Conclusion:</b><i> </i>Lacks of funds, unavailability of drugs are the leading factors to regimen completion. This could be easily be addressed by the government. 展开更多
关键词 Hypertension NON-adherence MEDICATION Inhibiting Factors High Blood Pressure Patients characteristics
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不同入侵程度肿柄菊生态化学计量特征
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作者 罗娅婷 王春琪 +1 位作者 崔现亮 字应伟 《南方农业学报》 CAS CSCD 北大核心 2024年第5期1347-1354,共8页
【目的】研究不同入侵程度下肿柄菊植株不同器官及根际土壤化学计量特征,剖析肿柄菊资源利用和分配策略,为肿柄菊入侵防控提供理论参考。【方法】在云南省普洱市思茅区郊区公路边选取有肿柄菊入侵至少4年的研究样地,设15个试验区,包括5... 【目的】研究不同入侵程度下肿柄菊植株不同器官及根际土壤化学计量特征,剖析肿柄菊资源利用和分配策略,为肿柄菊入侵防控提供理论参考。【方法】在云南省普洱市思茅区郊区公路边选取有肿柄菊入侵至少4年的研究样地,设15个试验区,包括5个重度入侵区(肿柄菊盖度占70%以上)、5个中度入侵区(肿柄菊盖度占30%~70%)和5个轻度入侵区(肿柄菊盖度占30%以下),分别采集肿柄菊根、茎、叶样品及根际土壤样品,检测植株和土壤中全磷(TP)、全氮(TN)和有机碳(SOC)含量,并分析化学计量特征。【结果】随入侵程度的增加,肿柄菊生境土壤TN和SOC含量呈显著降低趋势(P<0.05,下同),而TP含量无显著变化(P>0.05,下同);从轻度入侵到重度入侵,TN含量下降54.2%,SOC含量下降53.1%,肿柄菊入侵地土壤SOC和TN贫乏。3种入侵程度的肿柄菊各器官TP和TN含量均为叶>根>茎,SOC含量为根>叶>茎。重度入侵有利于肿柄菊植株TP含量积累,轻度入侵有利于肿柄菊茎TN含量积累。从轻度入侵到重度入侵,肿柄菊根、茎C∶N显著升高,根、茎C∶P显著降低,茎N∶P显著降低;同一入侵程度的肿柄菊C∶N和C∶P均为茎>根>叶;N∶P在轻度入侵为叶>茎>根,在中度和重度入侵为叶>根>茎。入侵程度对肿柄菊TN和TP含量及C∶N、N∶P具有显著或极显著影响(P<0.01,下同),不同器官对肿柄菊SOC、TN和TP含量及C∶N、C∶P、N∶P均具有极显著影响;器官与入侵程度交互作用仅对N∶P有极显著影响,对其他指标无显著影响。肿柄菊根、茎与土壤的TP、TN和SOC含量及化学计量比之间部分存在显著或极显著相关性。【结论】肿柄菊入侵对研究样地的土壤产生一定影响,土壤的改变同时反馈于肿柄菊。肿柄菊将N、P元素更多分配给叶,C元素更多分配给根,生长受到N元素限制;肿柄菊的根和叶具有相对快速的生长能力,以扩张种群、增大入侵性。 展开更多
关键词 肿柄菊 入侵程度 生态化学计量特征 资源分配
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儿童侵袭性肺炎链球菌病伴坏死性肺炎临床特点、耐药性和预后不良相关因素分析
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作者 马晨 张祎 +2 位作者 李芳 王静 陈葳 《检验医学》 CAS 2024年第3期265-271,共7页
目的探讨儿童侵袭性肺炎链球菌病(IPD)伴坏死性肺炎(NP)临床特点、耐药性和预后不良相关因素。方法选取2018年6月—2022年6月西安交通大学第一附属医院IPD伴NP患儿158例(观察组),以同期92例肺炎支原体感染NP患儿作为对照组。比较2个组... 目的探讨儿童侵袭性肺炎链球菌病(IPD)伴坏死性肺炎(NP)临床特点、耐药性和预后不良相关因素。方法选取2018年6月—2022年6月西安交通大学第一附属医院IPD伴NP患儿158例(观察组),以同期92例肺炎支原体感染NP患儿作为对照组。比较2个组患儿临床特征和实验室相关指标检测结果。对肺炎链球菌进行体外药物敏感性试验。根据预后情况将IPD伴NP患儿分为预后不良组(26例)和预后良好组(132例)。采用多因素Logistic回归分析筛选IPD伴NP患儿预后不良的影响因素,并构建预测IPD伴NP患儿预后不良的列线图模型。采用受试者工作特征(ROC)曲线评价列线图模型的预测效能。结果观察组发热时间、气促发生率和C反应蛋白(CRP)、白细胞(WBC)计数、中性粒细胞绝对数(NEUT#)、肿瘤坏死因子α(TNF-α)、降钙素原(PCT)水平,以及胸腔积液乳酸脱氢酶(LDH)、WBC计数、葡萄糖水平均显著高于对照组(P<0.05)。肺炎链球菌对万古霉素、左氧氟沙星和利奈唑胺较敏感,对红霉素、克林霉素的敏感率较低。CRP>161.75 mg·L^(-1)、WBC计数>20.24×10^(9)/L、NEUT#>0.86×10^(9)/L、PCT>2.98μg·L^(-1)、血钠<2.24 mmol·L^(-1)、血钙<136.35 mmol·L^(-1)与IPD伴NP患儿预后不良有关(P<0.05)。结论IPD伴NP患儿发热时间长,易发生气促,感染菌株对万古霉素、左氧氟沙星和利奈唑胺较敏感。高水平CRP、WBC、NEUT#、PCT和低水平血钠、血钙与IPD伴NP患儿预后不良有关。 展开更多
关键词 侵袭性肺炎链球菌病 坏死性肺炎 临床特点 耐药性 预后
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儿童侵袭性流感嗜血杆菌感染的临床特征及血清学分型
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作者 孟晋华 李文玲 +3 位作者 孙志勇 郭超 范彧 朱镭 《中国感染控制杂志》 CAS CSCD 北大核心 2024年第6期700-705,共6页
目的分析儿童侵袭性流感嗜血杆菌(Hin)感染的临床特征及血清分型特点。方法回顾性分析2015—2021年山西省儿童医院收治的34例侵袭性Hin感染患儿的病例资料。根据临床诊断分为脑膜炎感染组和非脑膜炎感染组。分析患儿的一般资料、症状、... 目的分析儿童侵袭性流感嗜血杆菌(Hin)感染的临床特征及血清分型特点。方法回顾性分析2015—2021年山西省儿童医院收治的34例侵袭性Hin感染患儿的病例资料。根据临床诊断分为脑膜炎感染组和非脑膜炎感染组。分析患儿的一般资料、症状、体征、实验室血清学指标、Hin血清分型特点及两组间炎症因子水平的差异。结果34例患儿中男22例,女12例,男女比例为1.83∶1,≤36个月患儿占82.35%。脑膜炎感染组患儿降钙素原(PCT)为[23.71(4.10,77.80)]ng/mL、C反应蛋白(CRP)为[200.00(164.55,200.00)]mg/L,均高于非脑膜炎组[分别为1.08(0.49,6.00)ng/mL、69.46(48.09,125.63)mg/L],差异均具有统计学意义(均P<0.05)。血小板计数(PLT)非脑膜炎组[(312.56±186.81)×10^(9)/L]高于脑膜炎组[(183.28±165.67)×10^(9)/L],差异有统计学意义(P<0.05)。白细胞计数(WBC)和中性粒细胞百分比(NEUT)两组间比较,差异无统计学意义(均P>0.05)。分离的Hin菌株中,b型流感嗜血杆菌(Hib)27株,e型2株,f型2株,3株不可分型,未发现a、c、d血清型菌株。脑膜炎感染组与非脑膜炎感染组患儿可分型Hin菌株分布比较,差异无统计学意义(χ^(2)=0.25,P>0.05)。可分型Hin菌株在男、女患儿中的构成比(67.74%VS 32.26%)比较,差异无统计学意义(χ^(2)=1.42,P>0.05)。结论侵袭性Hin感染病例以3岁以内儿童居多,分离株以b型占优势,感染患儿CRP、PCT明显升高,PLT明显低于非感染患儿,对临床诊断有一定应用价值,可结合临床及其他检验项目为侵袭性感染疾病的早期分类诊断及抗感染治疗提供有效支持。 展开更多
关键词 流感嗜血杆菌 侵袭性感染 血清分型 临床特点 降钙素原 C反应蛋白
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云南九大高原湖泊湖滨带入侵植物物种组成与分布特征
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作者 张瑞东 吴富勤 +3 位作者 李坤冀 金彦杉 刘程霞 申仕康 《生态环境学报》 CSCD 北大核心 2024年第3期351-361,共11页
湖滨带植物多样性是湖滨带生态系统维持稳定的关键,入侵植物的出现破坏湖滨带生态平衡,对湖滨带生态安全造成威胁。为揭示云南九大高原湖泊湖滨带入侵植物组成与分布特征,基于文献报道及野外踏查,整理得到云南九大高原湖泊湖滨带外来入... 湖滨带植物多样性是湖滨带生态系统维持稳定的关键,入侵植物的出现破坏湖滨带生态平衡,对湖滨带生态安全造成威胁。为揭示云南九大高原湖泊湖滨带入侵植物组成与分布特征,基于文献报道及野外踏查,整理得到云南九大高原湖泊湖滨带外来入侵植物名录,并对其种类组成、原产地、生活型、分布特征、区系类型、繁殖特征进行了分析。结果显示,云南九大高原湖泊湖滨带有外来入侵植物64种,隶属于23科52属。从种类组成上看,外来入侵植物多为菊科(Asteraceae)和苋科(Amaranthaceae);从分布特征上看,滇池湖滨带入侵植物分布最多,泸沽湖湖滨带入侵植物分布最少;从原产地上看,超过50%的入侵植物来自美洲;从生活型上看,外来入侵植物几乎均为草本植物,且以一年生草本植物居多;从物种分布上看,白车轴草Trifolium repens、凤眼莲Eichhornia crassipes、土荆芥Dysphania ambrosioides、喜旱莲子草Alternanthera philoxeroides分布最广;从区系类型上看,九大高原湖泊湖滨带外来入侵植物科和属的区系类型均具有明显的广布与泛热带分布特征;从繁殖特征上看,外来入侵植物花期集中于7-10月,果实类型多为被毛瘦果。研究表明,云南九大高原湖泊湖滨带入侵植物较为多样,与同区域数据比对后发现九大高原湖泊湖滨带入侵植物种数有所增加。不同湖滨带入侵植物种数的差异可能与海拔、温度和周边人口数量有关,较高的海拔,较低的年均温以及较少的周边人口数量都有利于减少湖滨带入侵植物种数。研究结果将为高原湖泊湖滨带生态系统风险评估和防控部署提供理论基础。 展开更多
关键词 高原湖泊 湖滨带 入侵植物 物种组成 分布特征 生态安全 风险防控
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我国统筹金融发展和安全的路径、特征与逻辑
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作者 段世德 《金融理论探索》 2024年第2期23-31,共9页
我国的金融发展探索与实践,依托人民政权、运用市场规律和通过主动改革,形成统筹金融发展和安全的路径轨迹,走出了不同于西方国家的独特路径,支撑了经济发展并提升了国家竞争力。在统筹金融发展和安全的实践中,形成坚持党的领导,保障金... 我国的金融发展探索与实践,依托人民政权、运用市场规律和通过主动改革,形成统筹金融发展和安全的路径轨迹,走出了不同于西方国家的独特路径,支撑了经济发展并提升了国家竞争力。在统筹金融发展和安全的实践中,形成坚持党的领导,保障金融服务的公益性,重视国外的经验但不盲从,通过服务发展保障金融安全和坚持改革创新与有序渐进等鲜明特征。在理念进步和实践积累的基础上,形成了坚持人民性的宗旨、独立性的原则、畅通性的目的和系统性的策略的发展逻辑依循。要推动金融高质量发展并更好地服务现代化建设,既要总结历史经验形成科学的认识,又要结合发展的需要解放思想推动实践创新,才能取得更好的成效。 展开更多
关键词 金融发展 金融安全 路径轨迹 实践特征 逻辑依循
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电磁波击落无人机的机理剖析和验证
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作者 魏利郝 敦书波 +1 位作者 张旭 郑丹妹 《安全与电磁兼容》 2024年第5期51-55,共5页
民用无人机大量普及,飞行故障不断出现。为提高强电磁环境下无人机的电磁防护能力,快速准确定位敏感部件及干扰传播路径,提出一种无人机近场注入噪声技术方案,通过向无人机注入交变电场和磁场干扰,以重现无人机在强电磁环境下的跌落现... 民用无人机大量普及,飞行故障不断出现。为提高强电磁环境下无人机的电磁防护能力,快速准确定位敏感部件及干扰传播路径,提出一种无人机近场注入噪声技术方案,通过向无人机注入交变电场和磁场干扰,以重现无人机在强电磁环境下的跌落现象。文章介绍了敏感部件及敏感性质、干扰入侵路径、受扰阈值的确认方法,对无人机进行电磁防护加固措施的验证具有一定的参考意义。 展开更多
关键词 无人机 强电磁环境 近场注入 入侵路径 敏感性质 受扰阈值
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不同分子亚型浸润性乳腺癌乳腺X线摄影、弹性模量和超声特征差异及浸润性乳腺癌发病危险因素分析 被引量:1
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作者 陈香洁 周丽红 +2 位作者 江锦芳 罗颖 谢紫霞 《临床和实验医学杂志》 2024年第2期195-200,共6页
目的探究不同分子亚型浸润性乳腺癌的乳腺X线摄影、弹性模量和超声特征,并分析浸润性乳腺癌发病的危险因素。方法回顾性选取2020年1月至2022年1月在深圳市龙岗区妇幼保健院进行诊治的123例浸润性乳腺癌患者纳入研究,作为病例组。根据患... 目的探究不同分子亚型浸润性乳腺癌的乳腺X线摄影、弹性模量和超声特征,并分析浸润性乳腺癌发病的危险因素。方法回顾性选取2020年1月至2022年1月在深圳市龙岗区妇幼保健院进行诊治的123例浸润性乳腺癌患者纳入研究,作为病例组。根据患者病理学分子亚型结果分组:管腔A型33例(Luminal A组),管腔B型42例(Luminal B组),三阴型26例(三阴组),人类表皮生长因子受体2(HER-2)过表达型22例(HER-2过表达组)。对各组的乳腺X线摄影(肿块形态、肿块边缘、肿块密度、微钙化及钙化分布情况)、弹性模量[面积比、应变率比值、最大弹性模量(Emax)、最小弹性模量(Emin)、平均弹性模量(Emean)、Eradio值]和超声特征(边界特点、回声类型、形态是否规则、有无钙化、后方回声表现、有无高回声晕、生长方向及血流信号方面)进行记录和对比分析,另选择同期在本院进行健康体检的50名志愿者作为对照组,探究浸润性乳腺癌的发病危险因素。结果各组经乳腺X线摄影检查结果组间比较,差异无统计学意义(P>0.05)。对各组间患者的乳腺X线摄影特征进行比较,4组在肿块形态、肿块边缘、肿块密度、微钙化及钙化分布情况方面差异均有统计学意义(P<0.05)。Luminal A组与Luminal B组相比较,两组间面积比、应变率比值、Emax、Emin、Emean、Eradio值差异均无统计学意义(P>0.05);HER-2过表达组的上述指标均较Luminal A组、Luminal B组、三阴组高,三阴组较Luminal A组、Luminal B组低,差异均有统计学意义(P<0.05)。4组间多普勒超声特征在边界特点(毛刺状、清晰、微分叶)、回声类型、形态是否规则、有无钙化、后方回声表现、有无高回声晕、生长方向及血流信号方面比较,差异均有统计学意义(P<0.05)。单因素分析发现文化程度、绝经状态、职业、生育史及流产史等均可能会影响浸润性乳腺癌的发病(P<0.05)。多因素Logistic回归分析显示文化程度低及未生育为影响患者发生浸润性乳腺癌的危险因素。结论不同分子亚型浸润性乳腺癌患者的乳腺X线摄影、弹性模量和超声特征表现均存在差异,患者文化程度低及存在生育史会增加患者发生浸润性乳腺癌概率,应予以重视。 展开更多
关键词 乳腺X线摄影术 危险因素 浸润性乳腺癌 弹性模量 超声特征
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塔里木盆地库车坳陷克深气藏超深层致密砂岩储层天然裂缝发育特征及对水侵的影响
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作者 徐小童 曾联波 +6 位作者 董少群 第五鹏祥 李海明 刘剑忠 韩高松 徐辉 冀春秋 《石油实验地质》 CAS CSCD 北大核心 2024年第4期812-822,共11页
天然裂缝是影响塔里木盆地库车坳陷克深超深层致密砂岩气藏气井高产和水侵的重要因素,裂缝研究对明确气藏水侵规律及防控水政策的制定意义重大。通过岩心、铸体薄片、常规测井、成像测井、生产数据、试井等资料,研究了有效裂缝发育特征... 天然裂缝是影响塔里木盆地库车坳陷克深超深层致密砂岩气藏气井高产和水侵的重要因素,裂缝研究对明确气藏水侵规律及防控水政策的制定意义重大。通过岩心、铸体薄片、常规测井、成像测井、生产数据、试井等资料,研究了有效裂缝发育特征、分布规律及气藏水侵特征,探讨了不同缝网系统水侵的影响。高角度和近直立的剪切裂缝为该区最主要的裂缝类型。垂向上,巴什基奇克组一段多为全充填裂缝,为无效裂缝;巴二段和巴三段多为半—无充填裂缝,为有效裂缝。平面上,NNW—SSE向有效裂缝富集在气藏西部,且平均开度大;东部相对发育近E—W向、NWW—SEE向的有效裂缝,平均开度较小。有效裂缝越发育,开度越大,气井初期封存水的产出越低,多产出凝析水。从投产到见水,地层水呈封存水、凝析水、可动水、纯地层水等赋存形式产出。有效裂缝的发育程度,开度及走向是影响非均质水侵的重要因素。与水侵方向近平行的、密集的、高有效性的缝网系统会加快水侵速度,导致气井大量产水,严重降低气井产能。综合有效裂缝的发育特征和单井水侵特征,气藏呈现出边底水沿断裂/密集裂缝快速水窜型、边水沿稀疏裂缝缓慢锥进型、边底水缓慢抬升侵入型3种水侵模式。 展开更多
关键词 天然裂缝 水侵动态特征 水侵模式 超深层气藏 库车坳陷 塔里木盆地
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近红外无创血糖浓度的Label Sensitivity算法和支持向量机回归
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作者 孟琪 赵鹏 +4 位作者 宦克为 李野 姜志侠 张瀚文 周林华 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2024年第3期617-624,共8页
近红外光谱分析技术在生物医学工程领域具有广阔应用前景。无创且持续性地测量能实时监控人体血糖水平,给糖尿病患者带来极大便利性、提高生存质量、降低糖尿病并发症发生率具有很大的社会效益。无创血糖监测的想法提出较早,但仍然存在... 近红外光谱分析技术在生物医学工程领域具有广阔应用前景。无创且持续性地测量能实时监控人体血糖水平,给糖尿病患者带来极大便利性、提高生存质量、降低糖尿病并发症发生率具有很大的社会效益。无创血糖监测的想法提出较早,但仍然存在预测精度低、预测值与标签值相关性不高等难点,至今没有达到临床要求。近年来,光谱检测技术发展迅猛且机器学习技术在智能信息处理方面具有明显优势,两者结合可以有效提高人体无创血糖医学监测模型的精度和普适性。提出了一种标签敏感度算法(LS),并结合支持向量机方法建立了人体血糖含量预测模型。使用近红外光谱仪采集了4名志愿者食指处动态血液光谱数据(每名志愿者28组数据),并使用多元散射矫正(MSC)方法消除了部分光散射的影响。考虑血糖对不同波长光的吸收有差异,提出了基于血糖浓度标签差的特征波长挑选方法,并构建了标签敏感度支持向量机(LSSVR)预测模型。设计实验,对比该模型与偏最小二乘回归(PLSR)和区分度支持向量机(FSSVR)算法。结果表明,LS算法的最佳特征波长数为32,经特征波长选择后的LSSVR表现最佳,其均方误差降低至0.02 mmol·L^(-1),明显优于全谱段PLSR模型,血糖浓度的预测值与标签值的相关系数提升至99.8%,预测值全部位于可容许误差的克拉克网格A区内。LSSVR模型的优异表现为早日实现血糖的无创监测提供了新思路。 展开更多
关键词 无创血糖 近红外光谱 特征波长 Label Sensitivity算法 支持向量机
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缙云县外来入侵植物调查及分析
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作者 梅建平 王洁威 +2 位作者 何诗杨 饶琼 吴家森 《安徽农业科学》 CAS 2024年第6期145-149,共5页
通过对缙云县18个乡镇72个踏查点进行实地踏查,并结合文献资料,研究了缙云县外来植物的结构组成以及分布状况。结果显示,缙云县已存在的外来入侵植物共有59种,隶属25个科,48个属。其中,菊科是缙云县外来植物的主要类群,共20种,占总种数... 通过对缙云县18个乡镇72个踏查点进行实地踏查,并结合文献资料,研究了缙云县外来植物的结构组成以及分布状况。结果显示,缙云县已存在的外来入侵植物共有59种,隶属25个科,48个属。其中,菊科是缙云县外来植物的主要类群,共20种,占总种数的33.9%。此外,46种原产自美洲,占总数的78.0%。分布最广外来入侵植物是斑地锦、垂序商陆、凤仙花、空心莲子草、三叶鬼针草、胜红蓟、小蓬草。该研究为控制缙云县外来入侵物种提供数据支持,有利于制定对外来植物的防控策略,为缙云县的生态多样性和物种多样性保护提供理论依据和数据参考。 展开更多
关键词 外来入侵植物 缙云县 生态保护 分布特征
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加拿大一枝黄花和小飞蓬共同入侵对植物群落的影响
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作者 何孟莹 解青松 +4 位作者 李玥 尹宣懿 刘婷婷 龙依依 张震 《安徽农业大学学报》 CAS CSCD 2024年第3期359-367,共9页
为阐明两种入侵植物共同入侵下入侵植物和其他植物的共存机理,以加拿大一枝黄花(Solidago canadensis)和小飞蓬(Erigeron canadensis)共同入侵的植物群落为研究对象,通过样方调查法分析不同入侵程度条件下植物群落的组成、多样性、生态... 为阐明两种入侵植物共同入侵下入侵植物和其他植物的共存机理,以加拿大一枝黄花(Solidago canadensis)和小飞蓬(Erigeron canadensis)共同入侵的植物群落为研究对象,通过样方调查法分析不同入侵程度条件下植物群落的组成、多样性、生态位宽度和功能性状,阐释2种入侵植物共同入侵对地上植物群落多样性产生的影响。结果表明:(1)2种入侵植物在入侵地与未入侵地的植物群落组成存在一定的差异;与单一入侵相比,共同入侵增加了植物群落的植物种类数,增幅为20.00%~66.67%。(2)无论是单一入侵还是共同入侵,均显著降低了植物群落多样性,其中物种数目减少18.75%~37.50%;Shannon多样性指数降低29.33%~65.33%;Pielou均匀度指数降低38.60%~52.31%。(3)加拿大一枝黄花和小飞蓬共同入侵地的优势种比单一入侵地的多1~3种;共同入侵条件下,入侵种和伴生种间的生态位重叠度高于伴生种之间。(4)与单一入侵相比,共同入侵增加了共存植物种的5种功能性状:茎粗、叶面积、叶长、叶宽和地下生物量,也增加了2种入侵植物的叶面积和叶长,增幅分别为13.70%~684.95%和32.10%~71.55%。该研究表明加拿大一枝黄花和小飞蓬共同入侵拮抗性影响了植物群落多样性,可为阐明两种入侵植物共同入侵下的入侵植物和其他植物种的共存机理提供理论基础。 展开更多
关键词 共同入侵 加拿大一枝黄花 入侵植物 小蓬草 地上植被特征
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千岛湖外来物种蓝鳃太阳鱼的生活史特征及适应性
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作者 马玉兴 梁智策 +6 位作者 文峰 廖传松 盘家永 邵建强 何光喜 刘家寿 郭传波 《水生生物学报》 CAS CSCD 北大核心 2024年第9期1541-1552,共12页
为研究蓝鳃太阳鱼(Lepomis macrochirus)种群生活史特征及适应性,以千岛湖蓝鳃太阳鱼种群为研究对象,于2021年3月至2023年1月逐月采集样本共3484尾,系统研究了蓝鳃太阳鱼年龄、生长、繁殖和死亡等生活史特征及适应性。结果表明:千岛湖... 为研究蓝鳃太阳鱼(Lepomis macrochirus)种群生活史特征及适应性,以千岛湖蓝鳃太阳鱼种群为研究对象,于2021年3月至2023年1月逐月采集样本共3484尾,系统研究了蓝鳃太阳鱼年龄、生长、繁殖和死亡等生活史特征及适应性。结果表明:千岛湖蓝鳃太阳鱼的种群平均体长为(88±0.6)mm,平均体重为(30.42±0.53)g。其种群年龄结构简单,1—2龄的低龄个体占优势(83.97%)。通过拟合幂函数方程得到体长与体重关系式为BW=1×10^(–5)SL^(3.1543)(N=3484,R^(2)=0.97)。另外,千岛湖蓝鳃太阳鱼具有明显的雌雄异形现象,其繁殖季节为4—9月,绝对繁殖力为(11405±921)粒/尾,相对繁殖力为(282±14)粒/g,平均卵径为(0.74±0.003)mm。最后,利用Pauly经验公式和长度变换渔获曲线法分别估算出:自然死亡系数(M)为1.05,总死亡系数(Z)为3.58,捕捞死亡系数(F)为2.53,种群开发率(E)为0.71。综上,千岛湖蓝鳃太阳鱼的种群呈现出典型的r生活史对策,整体种群数量呈上升趋势,种群规模具有进一步扩张的潜在风险,亟需相应的管理和控制。与原产地北美及其他入侵地的种群相比,蓝鳃太阳鱼在繁殖时间及早期生长速度等的改变是其成功入侵千岛湖的关键适应性特征。研究结果补充了国内有关蓝鳃太阳鱼的种群生长特性、年龄结构和繁殖特征等基础资料,揭示了其在千岛湖入侵成功的适应性机制,为我国蓝鳃太阳鱼的入侵防控提供了重要的理论依据。 展开更多
关键词 千岛湖 蓝鳃太阳鱼 生物入侵 生活史策略 适应性特征
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